1. Technical Field
The present invention relates to a recording apparatus that performs recording on a recording medium.
In the present application, types of the recording apparatus include a serial printer that performs recording while a recording head moves in a predetermined direction; a line printer in which a recording head does not move; and a copy machine, a facsimile, and the like that have functions of the above printers.
2. Related Art
A recording apparatus that includes a medium support unit and a base body unit is widely used in the related art (JP-A-2012-25082). The medium support unit supports a recording medium in an area where recording is performed by a recording head. The base body unit supports both end portions of the medium support unit in a direction intersecting the transport direction of the recording medium.
The medium support unit (hereinafter, referred to as “platen”) is attached to the base body unit (hereinafter, referred to as “base”) by a vis in the recording apparatus disclosed in JP-A-2012-25082. The recording apparatus is configured to be capable of changing the deflection of a surface of the platen where the recording medium is supported depending on the fastening state of the vis.
The height of a bearing surface on which the vis abuts in the platen is formed differently in the rotation direction of the vis in the recording apparatus. That is, the bearing surface is configured of an abutment surface on which the vis abuts and a non-abutment surface. A force that presses down the platen occurs in the abutment surface, and a repulsive force from the platen occurs in the non-abutment surface when the vis is fastened on the platen. The forces that occur in the abutment surface and the non-abutment surface negate each other. Accordingly, deflection that occurs on the support surface of the platen can be controlled. Therefore, deflection of the platen can reside within an allowable range by adjusting the fastening state of the vis.
Here, it is necessary to check how the platen is deflected when the abutment surface and the non-abutment surface are formed in the recording apparatus. In addition, the fastening state (fastening force and the like) of the vis with respect to the platen is necessary to be managed. Furthermore, the material of the platen may be changed because of measures for recording quality on the recording medium.
The platen may be deformed more than expected depending on the material of the platen when the material of the platen is changed. Accordingly, in the recording apparatus disclosed in JP-A-2012-25082, even adjusting the fastening state of the vis may not be able to resolve deformation of the platen when the platen is deformed more than expected. As a consequence, a gap between the platen and the recording head may not be uniform in the direction intersecting the transport direction of the recording medium. Therefore, recording quality on the recording medium may be degraded, and failure may occur in transporting the recording medium.
Another recording apparatus used in the related art has a configuration in which a platen is configured as a roller-shaped member, and a sheet guide auxiliary plate configured of one plate-shaped member is configured so as to abut on the platen (refer to JP-A-2010-195540). A recording medium is transported along a transport path between the platen and the sheet guide auxiliary plate in the recording apparatus disclosed in JP-A-2010-195540. The sheet guide auxiliary plate presses the recording medium against the platen to help the roller-shaped platen transport the recording medium when the recording medium is transported between the platen and the sheet guide auxiliary plate.
Furthermore, a plurality of slits are formed along the axis direction of the roller-shaped platen in the sheet guide auxiliary plate. The slits divide the upper end of the sheet guide auxiliary plate into a plurality of guide pieces. According to this configuration, a guide piece in contact with the recording medium and a guide piece at a position away from the transport position of the recording medium each independently abut on the platen when the recording medium is transported by the platen. As a consequence, inclination of the entire sheet guide auxiliary plate caused by the thickness of the recording medium can be resolved since the guide piece in contact with the recording medium is independently operated. Therefore, recording is stably performed since the inclination of the sheet guide auxiliary plate can be controlled by the slits without being affected by the thickness or the size of the recording medium.
However, when the roller-shaped platen is bent in a direction intersecting the axis line direction of the platen and is deformed, the sheet guide auxiliary plate is bent along the axis line direction along with the deformation of the platen. Therefore, deformation of the platen cannot be reduced. As a consequence, deformation of the platen may cause failure to occur in transporting the recording medium.